Antarctica suffers long winter heatwave

The coldest continent on the planet recorded temperatures more than 3°C above seasonal norms.

It is the coldest continent on the planet. And yet, Antarctica also experiences an exceptionally long heatwave during its winter, according to the British institute specializing in the study of the polar regions. “The duration of this heat period is unusual”underlined to AFP Thomas Caton Harrison, expert at the British Antarctic Survey, Tuesday August 13.

In July, average temperatures on the southern continent were 3.1°C above seasonal norms, he said. That made it the second warmest July since records began in 1979, after July 1981. Average daily temperatures ranged from -34.68°C on July 15 to -28.12°C on July 31, according to data posted online by the University of Maine. The average temperature on the continent was -26.6°C on August 7, the latest date available. The anomaly in July even reached +9 to +10°C over a limited region that includes Queen Maud Land and part of the Weddell Sea.

Temperature anomalies are common during the Antarctic winter, but this episode is unusual in its duration, scientists say. It is the prolonged warmth that is “outstanding”insists Thomas Caton Harrison. “Very preliminary data suggest we may be on track for an exceptionally warm Antarctic winter”he adds.

The windswept, white continent with no permanent population is the coldest place on Earth. But it is also being affected by global warming. In a study published in June in the journal Nature Geoscience, researchers estimated that a new “tipping point” could be about to be crossed, with Antarctica heading towards a “uncontrolled melting” of its ice caps due to warmer ocean water. This poses a risk of rising sea levels as accelerated melting outpaces the formation of new ice on the continent, threatening coastal populations around the world.